Subcutaneous and systemic fungi

Question 1

Subcutaneous and system infections fungi

Answer 1

• all are primary respiratory pathogens-> initiated in lungs
• form DIMORPHIC fungi
• mold form in soil
• yeast form once spores are inhaled
• NOT communicable
• most lung infections are asymptomatic and self limitied

Question 2

Sporothrix schenckii

Answer 2

• enter skin via trauma
• sphagnum mass, hay, plant material, soil
• mycosis of implantation, can inhale conidia-> pulmonary infection

Question 3

Sporothrix schenckii diseases

Answer 3

Sporotrichosis

• lymphocutaneous (inflamed subQ nodules)-> nodule on finger/hand/arm, along lymphatic channel
• Pulmonary
• Osteoarticular (seeding of bones)
• Disseminated-> AIDS

Question 4

Sporothrix schencki treatment

Answer 4

Itraconazole/fluconazole (cutaneous lesion)
amphotericin B (lymph, pulmonary, disseminated)
-wear gloves, long sleeves, avoid contact with moss

Question 5

Coccidiodes immitis

Answer 5

Southwestern U.S (texas, arizona, california, south america)

• desert soil enhanced by rodent/bat droppings
• rain enhances cycle
• KOH to see spherules
• serological tests: mycelial phase antigen-> coccidioidin to detect AB: IgM & IgG appear later
• elevated IgG-> disseminated

Question 6

Coccidiodes immitis diseases

Answer 6

Primary pulmonary coccidioimycosis

• symptomatic respiratory syndrome-> inhale arthrospores
• chronic coccidioimycosis-> IC’s (elderly, HIV), cavity nodule formation
• disseminated coccidioimycosis-> elderly, AIDS, pregnancy, nonpruritic rash, erythema nodosum, erythema multiforme, coccidioidal meningitis, migratory anthralgias , desert rheumatism
• amphotericin B, itraconazole, oral fluconazole

Question 7

Histoplasma capsulatum var capsulatum/duboisii

Answer 7

• ohio/mississippi, central eastern US
• Mycotic infection
• grow in soil, chicken coops, only bats get infected
• IC’s, smokers, AIDS
• raking, bulldozing, caves, decaying buildings
• serology: antigen to detect capsular antigen (blood, urine, CSF)
• X-ray show abnormal chest X-ray
• itraconazole, amphotericin B

Question 8

Histplasma disease

Answer 8

Acute asymptomatic pulmonary
acute symptomatic pulmonary
chronic pulmonary
disseminated-> mouth sores, skin lesions
In immunosuppressed-> inhaled spore-> engulfed by MQ-> develop into yeast-> survive INSIDE PHAGOLYSOSOME-> disseminated in reticuloendothelial tissue-> granulomatous lesions-> death

Question 9

Blastomyces dermatitidis

Answer 9

South east and SC north america (ohio and mississippi river)

• outbreaks near rivers, collecting wood, tearing down old buildings
• common in dogs (not transmitted)
• culture-> colonies develop on enriched media (37 for 2 weeks)
• serology not helpful
• see under microscope

Question 10

Blastomyces dermititidis diseases

Answer 10

acute pulmonary (mimic bacterial pneumonia (TB))
disseminated-> skin, blood, bone
-prostate, kidneys, testes
-disseminated-> granulomatous disease
-itraconazole, fluconazole
-amphotericin B in severe cases